The recent trend in the design of communication devices or portable radios, such as hand held transceivers and selective call paging receivers has been to reduce the overall size of the radio and to add more functions and options. When more functions are added, however, additional controls must be provided to permit the user to select a particular operating parameter. But adding controls conflicts with the trend towards smaller radios, since there is less space available to add additional switches and other control devices.
Conventionally, the user's time to activate a menu or variable function parameter selection is saved by dividing the various functions, modes, or parameter features among multiple menu keys. The quickest and most convenient way to select a particular function would be to use an individual key for each system operation, mode, parameter, or feature. This approach however has the disadvantage that it requires many keys and therefore a large area to be implemented. In portable two-way units or paging receivers "real estate" is at a premium.
To increase the number of selectable functions, while reducing the number of switches, a radio controller or microcomputer could be designed to include a menu of possible function parameters that could be selected by scrolling or sequentially stepping through the menu by the selector's activation of one or more switches. Initially, a "menu" switch could be scrolled to select the menu item. Then another switch would scroll "up" (i.e. from the last entry in the menu toward the first) while a third switch would scroll "down" from the first entry towards the last. A display could be positioned on the top or elsewhere of the radio to indicate the particular parameter selected.
However, as market demands strive for the development of radios with more features and modes of operation for a user to select from, it will take much longer for the desired or selected feature or mode of operation to be reached by scrolling, since many undesired features or modes will have to be traversed first.
Therefore a need arises to provide a convenient method while saving real estate for the selection of features, functions, or modes using a minimum of keys. In addition, less keys present would also enable single-hand menu selection, which may be beneficial to a handicapped person or machine operator.